racingrev

Since i bought my 99 SS there has been an intermittent hesitation between 2-3500 rpm. I have checked my plugs, wires (they are all good), changed my fuel filter, cleaned air filter, run a few tanks of injector cleaner through it and I can not make the hesitation go away.

My friend plugged in a computer and it is not throwing any codes.

I took it to a local mechanic and he said nothing is wrong with it.

The car is stock other than the plugs and wires have been changed to msd and there are msd coil packs added.

Also the exhaust has been changed from the cats back to allow for the four out the middle look in the rear.

Any ideas what could be causing this problem?

Would appreciate help if anyone has had this experience!!

joesal68

Had a similar issue, I would check the vaccum lines. I swore up and down mine were good until i removed the entire system and found that the rubber grommets were rotting. Ireplaced it with new fuel line hose, Runs like a champ

dhctss

iTrader: (3)

My car did same when i bought. I replaced maf sensor problem solved. It would hesitate same rpms. Sometimes you can clean but mine someone bent the sensir wires

fstr n u

I had the exact same issue and spent the last year off and on problem solving my camaro's hesitation issue between 2 and 3k rpms.

1. Make sure there isn't too much di-electric grease on your sparkplug to sparkplug wire connections

2. Double check your battery grounds

3. Could be a Throttle position sensor (i replaced mine and that wasn't my issue)

4. Double check the gap on your spark plugs

5. Where were your 02 sensors last changed? If they are old, replace them.

6. Even though your spark plugs and wires were just changed, i would swap around ALL of your spark plug wires...very easy to do and double check that they feel as though there is a good connection between them...sometimes the metal connector from wire to spark plug is loose enough to cause that exact problem.

7. Clean your MAF with electrical connector cleaner and allow to dry properly before running.

Chaotic Deconstruct

I had a similar issue and it was a small tear in the spark plug boot causing it to arc of the exhaust manifolds. It was a new boot that apparently cracked under heat after only a few thousand miles so it can happen.

fruitsalad

iTrader: (5)

I've heard the MSD coil packs can cause more issues than the stockers.

racingrev

Thanks all for your great input, that gives me a few more things to check!

Also found a small leak in vac line. Changed it over and thought that would fix it. Seemed to temporarily solve then it came back. Maybe I will keep checking along those lines...perhaps there is another leak.

The MAF was quick and easy so now is cleaned and replaced..sadly not the issue. I will keep trying.